Role of Spatially Fractionated Radiotherapy (LATTICE) Treatment in Inoperable Bulky Soft-Tissue Sarcomas

Area of Science:

• Oncology
• Radiation Oncology
• Surgical Oncology

Background:

• Limited clinical outcomes for inoperable sarcoma patients treated with LATTICE (LRT).
• Need for evaluating LRT in non-extremity sarcomas with no other treatment options.

Purpose of the Study:

• To report treatment response, overall survival (OS), local-recurrence free survival (LRFS), and toxicity of LRT in inoperable sarcoma.
• To assess the feasibility and tolerability of LRT in bulky soft-tissue sarcomas.

Main Methods:

• Retrospective observational study of 15 inoperable non-extremity sarcoma patients (2020-2024).
• Treatment involved LATTICE (LRT) combined with external beam radiotherapy.
• Response evaluated by RECIST1.1, toxicity by CTCAE 5.0, survival by Kaplan-Meier curves.

Main Results:

• Median follow-up of 10 months.
• 67% of patients achieved stable local disease at 1-2 months post-treatment.
• Surgical resection was feasible in 5 patients; 3 are alive without disease.
• G2 toxicity reported in 3 patients; G3 toxicity in 2 patients (esophagitis, inguinal dermatitis).
• No G4-G5 toxicity observed.

Conclusions:

• LATTICE (LRT) is a feasible and well-tolerated radiation technique for inoperable bulky soft-tissue sarcomas.
• LRT demonstrates potential for managing local disease and improving outcomes in select sarcoma patients.
• Further studies are needed to define optimal protocols for palliative or preoperative LRT.